// Copyright 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CC_RESOURCES_SCOPED_UI_RESOURCE_H_
#define CC_RESOURCES_SCOPED_UI_RESOURCE_H_

#include "base/macros.h"
#include "base/memory/ref_counted.h"
#include "cc/base/cc_export.h"
#include "cc/resources/ui_resource_bitmap.h"
#include "cc/resources/ui_resource_client.h"

namespace cc {

class UIResourceManager;

// ScopedUIResource creates an UIResource from a bitmap and a LayerTreeHost.
// This class holds a pointer to the host so that when the instance goes out of
// scope, the created resource is deleted.  On a GetBitmap call from the
// UIResource manager, ScopeUIResource always returns the reference to the
// initially given bitmap regardless of whether the request was due to lost
// resource or not.
class CC_EXPORT ScopedUIResource : public UIResourceClient {
public:
    static std::unique_ptr<ScopedUIResource> Create(
        UIResourceManager* ui_resource_manager,
        const UIResourceBitmap& bitmap);
    ~ScopedUIResource() override;

    // UIResourceClient implementation.
    UIResourceBitmap GetBitmap(UIResourceId uid, bool resource_lost) override;
    UIResourceId id() { return id_; }

    // Returns the memory usage of the bitmap.
    size_t EstimateMemoryUsage() const { return bitmap_.EstimateMemoryUsage(); }

protected:
    ScopedUIResource(UIResourceManager* ui_resource_manager,
        const UIResourceBitmap& bitmap);

    UIResourceBitmap bitmap_;
    UIResourceManager* ui_resource_manager_;
    UIResourceId id_;

private:
    DISALLOW_COPY_AND_ASSIGN(ScopedUIResource);
};

} // namespace cc

#endif // CC_RESOURCES_SCOPED_UI_RESOURCE_H_
